MADRID — The U.S. Defense Department is looking to broaden its defense cooperation in Western Europe by deepening its military-to-military engagements, especially in maritime and cyber security initiatives.

U.S. Defense Secretary Leon Panetta, who is in the middle of a weeklong trip to four European capitals, called for greater cooperation in these and other areas during meetings with the defense ministers from Spain and Portugal.

“Our discussion today focused on how to expand the defense cooperation in new ways to meet the challenges of the 21st century,” Panetta said after his Jan. 15 meeting with Defense Minister Pedro Morenès in Madrid.

More from Panetta’s trip:

 Panetta Attends Ceremony with Pope (1/16)

 DoD To Delay USAF Personnel Reduction at Portuguese base (1/15)

Panetta specifically called for greater military partnerships to “strengthen our capabilities” in cyber security.

“What can we do both bilaterally and through NATO to try to strengthen our capability in the cyber arena,” he said.

He also called for a deeper maritime security partnership with Madrid that builds on the forward deployment of four U.S. Navy Aegis destroyers in Rota, Spain, which is near the western entry point to the Mediterranean Sea.

“Our decision to move ahead with this new deployment at a time of significant fiscal pressures … reflects our belief that the trans-Atlantic alliance will remain critical for global security in the 21st century and that we must make investments in order to keep it strong for the future,” he said.

Using a rotational deployment construct in regions around the world, as opposed to permanent basing, is a key tenet of the Pentagon’s year-old military strategy.

Earlier in the day, in Portugal, Panetta said DoD is looking to expand training and exercises between U.S. special operations forces and the Portuguese military.

These exercises, Panetta said after a meeting with Portuguese Defense Minister Josè Pedro Aguiar-Branco, “will enhance our shared efforts to build partner capacity in the region and beyond.”

In addition, U.S. aircraft carriers and other naval ships will continue making port visits in Portugal. The USS Harry Truman carrier group will stop in Portugal in the coming weeks.